diff --git a/mondumas/__init__.py b/mondumas/__init__.py
index bf6398d..683c9c4 100644
--- a/mondumas/__init__.py
+++ b/mondumas/__init__.py
@@ -2,7 +2,7 @@ from pyramid.authentication import AuthTktAuthenticationPolicy
 from pyramid.authorization import ACLAuthorizationPolicy
 from pyramid.config import Configurator
 from pyramid_mailer import mailer_factory_from_settings
-from pyramid.session import UnencryptedCookieSessionFactoryConfig
+from pyramid.session import SignedCookieSessionFactory
 from .security import groupfinder
 
 from .security import groupfinder
@@ -12,7 +12,7 @@ def main(global_config, **settings):
     """ This function returns a Pyramid WSGI application.
     """
     # declarations
-    session_factory = UnencryptedCookieSessionFactoryConfig('Ty6sIUe9')
+    session_factory = SignedCookieSessionFactory('Ty6sIUe9')
     authn_policy = AuthTktAuthenticationPolicy('Ty6sIUe8', callback=groupfinder, hashalg='sha512')
     authz_policy = ACLAuthorizationPolicy()
     mailer_factory_from_settings(settings)